The present invention relates to methods and apparatus for the preparation of grinding wheels with a treatment cylinder and methods and apparatus for performing grinding operations therewith. More particularly, the present invention is directed to techniques for selectively profiling a grinding wheel to enable various stages of a grinding operation to be performed at a single station where the grinding wheel may be reconfigured for differing functions between different stages in the operation.
The preparation of grinding wheels is generally performed by conventional methods which basically differ according to the circumferential speed relationship employed between the treatment cylinder and grinding wheel, the contact pressure relied upon, and the type of treatment cylinder used.
With the so-called crushing with a crushing cylinder, the circumferential speed r.sub.R .multidot.w.sub.R of the cylinder is made equal to the circumferential speed r.sub.S .multidot.w.sub.S of the grinding wheel. A substantial pressure, great enough to exceed the crushing strength of the binding material of the grinding wheel, is applied between the cylinder and the grinding wheel to cause single grains to be broken off of the grinding wheel. Due to this pressure, the grinding wheel is worked off to the negative form of the crushing cylinder. Therefore, the consistency of the surface of the grinding wheel, which corresponds to the graining of the grinding wheel, cannot be influenced. It is relatively rough and results in a correspondingly rough surface on the work piece in the grinding process.
In the second method, used as a supplement to the first, a diamond studded treatment cylinder or so-called diamond cylinder is used. The diamond cylinder is rotated with a speed which differs from that of the grinding wheel so that, contrary to the first method, the relative movement causes the diamonds to cut the grinding wheel grains. With this method, the resulting grinding wheel surface is considerably smoother than that achieved with the first method, with the relative smoothness of the surface being a function of the relative speed relationship selected. While each technique has advantages, the multiple steps involved, coupled with the varying procedures employed, render the resulting process costly and highly complex and do not allow convenient incorporation as an integral part of the grinding process.
Therefore, it is a principal object of the present invention to provide methods and apparatus for combining into a single technique, using a single treatment cylinder, the relative advantages of each of the two conventional methods of preparing grinding wheels and to adapt the same so that it may readily be incorporated within equipments for performing grinding operations. Various other objects of the present invention will become clear from the following detailed description of several exemplary embodiments thereof and the novel features will be particularly pointed out in conjunction with the claims appended hereto.